purine riboside

adenine atom atomic atoms base biochemistry biology bond bromodeoxyuridine carbon chain chemical chemistry compound cyclic cytosine deoxyribonucleic deoxyribose dna gene genetic guanin guanine helix hydrogen iododeoxyuridine isolated line metabolism model molecular molecule monophospate nitrogen nitrogenous nucleic organic oxygen phosphate print purine pyrimidine ribose riboside rna science structure substance thymidin thymine vector